For powering devices there is now a plethora of options at USB voltage (5v). My favorite are here:
voltaicsystems.com/6-watt-kit. They work fine directly with the Prop Activity Board.
But many of my students have a BOE, BOEBot or Homework. These BS2 boards are set up for 6-9v. Has anyone tried running BS2 boards at USB voltage? I'll give a try to stripping out a USB cable and soldering its power leads to a jack (or 9v clip). Any thoughts on a adding a buck-up from 5v to 7v?
There are lots of discussions here about rigging up solar, supercaps, battery charging schemes, etc. But they ecosystem is well developed for USB power. It would be great to have a plug-n-play solution.